One thing I have noticed is that I very, very seldom remember to “like” a main post that I, erm, well, like.
I assume that this is mostly explained by noting that I am self-centered sociopath, but I think there are some interface reasons for it as well.
It might be nice if on the main article pages along with the (new?) social media share bar there was a button in the bar to “Like” the article. (Also, the share bar should be repeated at the end of long articles, since that is where I am when I would theoretically make a decision to share it). Also the permalink section of the thread in BBS has so much empty space that it seems a shame not to use that to better call out the option to “like” the main post.
This is all assuming that the use of the “Like” button for an article actually provides any kind of valuable feedback to the editors/authors.